1. Field of the Invention
The present invention generally relates to a sofa convertible into a bed.
2. Description of the Related Art
The document EP-A-811341 by the same Applicant discloses a sofa convertible into a bed in which the mattress in the sofa configuration is folded underneath the sliding support structure. In this known solution, the stationary support structure of the sofa-bed comprises a backrest structure borne by two support arms which are connected to the rear support legs of the sofa. The backrest structure is capable of assuming a vertical configuration in which it forms the head of the bed or a rearwards folded configuration forming the backrest of the sofa.
The documents U.S. Pat. No. 2,568,366 and U.S. Pat. No. 4,586,206 describe sofas convertible into beds with the characteristics contained in the preamble of the main claim. In both these known solutions, the mattress is movable relative to a support and structure guide between a bed configuration in which the mattress extends horizontally and a sofa configuration in which an upper portion of the mattress is folded upwards relative to a lower portion. The support structure of the sofa comprises a stationary backrest structure with a rear wall and a front wall, mutually distanced and defining a compartment which, in the sofa configuration, receives the upper portion of the mattress.